Unit 4: Chemistry - Density and Property Changes

Question 1

Metric System

Mass (units)

Answer 1

-Kilograms (kg)
-Grams (g)
-Scale

Question 2

Metric System

Volume (units)

Answer 2

Regular shaped object:
-cm(cubed)
-Ruler
Irregular shaped object:
-Water Displacement Method
-1mL = 1cm(cubed)
-Graduated cylindar

Question 3

Qualitative Property

Answer 3

-Don’t find exact measurements
-Words
-Observed
-Only look/feel matter

Question 4

Quantitative Property

Answer 4

-Find exact number/measurement
-Numbers
-Tools

Question 5

Mass

Answer 5

Amount of particles in substance
-Quantitative
Mass vs. Weight
-Mass does not change
-Weight pull of gravity on matter, does change

Question 6

Volume

Answer 6

Amount of space substance takes up
-Quantitative

Question 7

Irregular Shaped Object Volume Measurement

Answer 7

Water Displacement Method:
-Used for irregular shapes
Steps:
1. Filll grad. cylindar with water
2. Water measurement
3. Object in cylindar + take measurement
4. Subtract water with object from initial water

Question 8

Relationship Between Mass and Volume

Answer 8

-Higher volume does not mean a higher mass
ex.
Metal Block:
Mass - 43.8g
Volume - 15.6 cm(cubed)
Water:
Mass - 25g
Volume - 25mL
*Block had a greater mass than the water, but it had a lesser volume than the water

Question 9

Density

Answer 9

-Amount of particles in a cubic centimeter
-Each matter has unique density
-Ratio between mass and volume
-Physical property
*More close together = higher density
How to find density:
mass/volume = density
D = g/cm(cubed)

Question 10

What happens to the matter’s density if you cut up the substance?

Answer 10

*Stays the same because it is mass PER cm(cubed)
Density is used to identify material of substance

Question 11

What is the affect of water’s density on other substances and whether it can float or not?

Answer 11

Water’s Density - 1g/cm(cubed)
-Substance’s density higher than water’s density = sinks
-Substance’s density lower than water’s density = floats
-Substance’s density closer to water’s density but below = water will cover object more
-Substance’s density farther to water’s density but below = water will cover object more

Question 12

Does air take up space?

Answer 12

Yes
Demostrations:
Funnel Test - water didn’t go to beaker beucase stopper sealing edges
Connected Syringes - push one syringe, other syringe goes up because air moves to syringe

Question 13

Why is the air inivisible?

Answer 13

-Molecules too small to see
-Molecules so spread out
For a solid, even though molecules too small to see, still very close together

Question 14

What is the density of water?

Answer 14

1g/cm(cubed)

Question 15

9.2 grams and 2.05 cm(cubed)
What is the substance?

Answer 15

4.49g/cn(cubed)
Titanium

Question 16

120g and 10.6 cm(cubed)
What is the substance?

Answer 16

11.32g/cm(cubed)
Lead

Question 17

13.1 cm(cubed) and 253g
What is the substance?

Answer 17

19.3g/cm(cubed)
Gold

Question 18

The density of a substance is 40g/cm(cubed).
The mass of a substance is 8g
What is the volume?

Answer 18

5cm(cubed)

Question 19

Chemical Properties

Answer 19

How substance’s changes or appearance changes

Question 20

Flammability

Answer 20

Matter that can burn
-Wood
-chips (oil)

Question 21

Oxidation

Answer 21

Substance exposed to air + air causes color change
-Rusting
-Apple

Question 22

Reactivity

Answer 22

Substance reacts to another substance
-Substance + acid –> solid dissolved

Question 23

What are some properties you can use to identify a substance?

Answer 23

Physical properties:
-Quantitavie + Qualitative
Density:
-substance has unquie density
Chemical properties:
-whether it burns, changes color, or reacts to acid
Conductivity:
-transfer of thermal energy through contact
Boiling + Melting Points:
-matter changes to different state
-unique melting + boiling point
Solubility:
-substance dissolved in water

Question 24

Physical Property

Answer 24

-Can be measured
-Matter stays the same
-Mass, volume, density, etc.